Reading a newspaper that has previously been handled by a person from another household, a custom in bars and cafés, can essentially be considered a safe habit, if going by the scientific evidence.
The probability of transmission of the SARS-CoV-2 coronavirus, the pathogen that causes covid, after touching a contaminated object is less than 1 in 10,000, according to a report published on 5 April by the US Centers for Disease Control (CDC). In addition, the high porosity of newsprint further reduces this low probability of transmission.
A year and a half after the outbreak of this virus, knowledge of the mechanisms of contagion has come a long way. Images of consumers disinfecting food containers before putting away their supermarket shopping are a thing of the past.
The scientific community has proven the significance of airborne transmission, something that the World Health Organisation denied at the beginning of the pandemic and which still generates resistance. What scientists fully agree on is the limited relevance of transmission by fomites – objects and surfaces – of SARS-CoV-2.
Non-porous surfaces
According to studies cited by the US CDC, the existence of viable virus is highest on non-porous surfaces, such as metals, plastic and glass, but this is reduced to minutes on porous surfaces, such as newsprint, where the virus is inactivated more quickly. This could be attributed to the capillary action of the pores – the absorption effect we see when we dip the end of a piece of kitchen towel into a liquid and watch it move through it – and the faster evaporation of aerosol droplets. And all this under laboratory conditions. In real life, normal hygiene habits, heat, ventilation and sunlight contribute to further degradation of this virus.
Paper envelopes reduce microbial viability
An example of the reduced viability of microbes on paper is the recommendation by scientists to store reusable face masks in paper envelopes rather than in plastic bags or steel or glass containers. Among the world reference bodies that recommend storing masks in envelopes are the US Centers for Disease Control (CDC). rafa lópez
As early as July 2020, Emanuel Goldman, Professor of Microbiology at Rutgers University (USA), wrote in The Lancet that “the possibility of transmission via inanimate surfaces is very small, and only in cases where an infected person coughs or sneezes on the surface and someone else touches that surface shortly thereafter”.
In September, a study published in the same scientific journal and conducted in a hospital setting by Italian researchers indicated that there is a low risk of transmission of this coronavirus via fomites under real-life conditions, provided that cleaning procedures are followed.
As José Luis Jiménez, Professor of Chemistry at the University of Colorado (USA) and a world reference in aerosols, has reminded us on several occasions, other viruses that have a lipid envelope, like SARS-CoV-2, do not survive for long on our hands, so to become infected with this coronavirus a person would have to touch their eyes, nostrils or mouth shortly after touching a contaminated surface, a gesture that is largely prevented by using a mask.
Experts stress that hand washing is a highly recommended hygiene habit to prevent a wide range of infectious diseases, although its ability to limit the spread of covid is considered much lower than other measures, such as social distancing, the use of well-fitting masks and good ventilation. For example, an intensive hand-washing programme in the UK reduced transmission by 16%.
A recent scientific paper published in The Lancet and signed by José Luis Jiménez and other scientists provided 10 pieces of evidence for the importance of airborne transmission of the coronavirus, one of which is the scant evidence in support of large droplets and fomites. Therefore, leafing through a newspaper or a book read beforehand by other people cannot be considered a risky practice.